Welding-machine.



J. H. GRAVELL.

WELDING MACHINE. APPLIGATION FILED T15R24, 191s,

Patented m. 13, 1914.

2 SHEETS-SHEET 1.

INVENTOR WITNESSES 7 ATTORNEY J. H. GRAVELL.

WELDING MACHINE.

APPLICATION FILED FEB. 24, 1913.

lNI/ENTDR ATTORNEY 2 SHEETS-SHEET 2.

Patented Jan. 13, 1914.

WITNESSES I 25 latter could be made of small size andweight.

Jaints 1i; -'GRAVELL, or PHILADELP U D STArns j trEuT oFricE.

HIA, PENNSYLVANIA, ASSIGNOB '10' HALE AND.

KILBITBN COMPANY, OF -IEHIIAADELIPIHIA, PENNSYLVANIA, A CORPORATION OF DELAWARE. 3

Specification of Letters Patent.

WELDING-MACHINE.

Patented Jan. 13, 1914.

I Application filed February 24, 1913, Serial No. 750,059.

To all whom it may concern:

Be it known that I, JAMES H. GRAVELL, a

-citizen of the United States,\re siding at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Welding-.Machinesg of which the following is a specification.

- This invention relatesto electric welding machines and is directed to the provision o a machine of this character of an improved constructionfthe improvements being of particular utility in the construction of a machine of suchsmall size and weight compared to its capacity as to render the ma-' chine portable.

In electric welding operations it has been 7 usual heretofore to manipulate the work rather than the machine while making a serles of welds, but in many cases the work or one or more of the parts thereof are of such weight or bulk as to permit of their a manipulation only with great difiiculty. In

operating on such parts, it would be far more convenient to movethe machine if the ,Q',';Ihe present invention involves the provision of a machine so constructed as to be of very small size and therefore portable,

One feature of the invention involves the useof the secondary-of the transformer as the frameofthe machine about which the several parts of the machine are grouped 7 This is accomplished by making the secondary in two-or more-parts and'connecting together two adjacent parts by means of a connecting member which lies on the side of the core opposite the seconda itself. These and other features 0 the invention aretset forth fully in the following description of a form of machine which embodies the invention, this machine. being illustrated in the accompanying drawings.

In these drawings, Figure 1 is a plan View of the machine with the inclosingcas ing' in section. Fig. 2 is atransverse sec tional view of the machine and Figs. 3 and" I 4 are top and side views of of the transformer.

Referring to these drawings, the seconda of the transformer is shown at 5 and this secondary constitutes the frameupon which the parts of the machine are .assembled. This secondary is a casting of copper and is of annular shape as shown in Fig. 3. The cross-sectional shape of this casting is illus' the secondary :trated in Fig. 2, from which it ap. ears that the casting has the cross-sections. shape of approximately two thirds of a tube. On one side the castin -5 has a lug 6 formed integral therewith. Directly below the lug 6, the secondary casting has a lug 7 formed integral-therewith and extended a substantial distance beyond the lug 6. Directly o posite the lugs 6 and 7 two lugs 8 and 9 are ormed to. i.

integral with the secondary castin 5. Between these two pairs of lugs, ot er pairs of lugs 10 integral with the secondary casting maybe provided for use in cooling the apparatus as hereinafter described. The secondary casting shaped as thus described and cut as hereinafter set forth, has insulating material 11' applied thereto over its outer curved surface, that is, over the semi-circular concave surfaceon the exterior of the annulus forming the secondary. This having been done, the core 12 is applied to the secondary 5. This core consists of a windin of wire. In forming this core, wire is woun around the secondary 5 in the concave circumferential groove thereof until a core 12 is built up circular in cross-section-and of a diameter equal to the diameter of the" conlar secondary. Insulating material 13 is then applied to the outer surface of the core 12.

Theprimary coils of the transformer consist of wire wound around the secondary and core made as .above set forth. These primary coils are-shown at 14 in Figs. 1 and 2 from which it will be seen that they are cave depression in the exterior of the annubuilt up in the form of sectors of a circle,

each convolution of the wire passing through the opening. in the annular secondary.

The welding terminals are secured to the lugs 6 and 7. For this purpose a frame or casting 15 is secured by bolts 16 to the lug 6. This frame 15 is extended downwardly and provided with a portion 17, which extends under the lug 7 and is secured to the lug 7 by means of a bolt 18. This portion 17 is, however, insulated from the h1g7 and screw 18 by suitable insulating material as'shown as'19. The frame 15 is provided with upwardly extending wings in which are formed .bearings for a short shaft 20 on which a disk 21 is adapted to rotate.

' thereto.

The opposite terminal of the machine consists of a bar 25 secured by screws 26 to the lug 7. A link 27 is pivotally connected to the terminal 23 at one end and is adapted to have the opposite end connected by means of a stud -28 to the disk 21. This disk is provided with a plurality of openings into any one of which the stud 28 may be inserted in adjusting the machine for different 3 kinds of work.

Theseconda-ry' casting 5 is so constructed as tov form two turns or convolutions about the core 12.; This is effected by making the secondary 5, constructed as above set forth, in two or more parts. Thiscan be most conveniently done by casting the secondary in one part and afterward cutting it in a predetermined manner. One of these cuts is indicated at 29 in Figs. 3 and 4. This cut extends entirely through the secondary casting 5 and is inclined in such a manner thatv the lugs 6 and 7, which lie one directly above the other, are onbpposite sides of the out. A similar inclined cut is'made through the secondary casting 5 at'a diametrically opposite point, as indicated at '30 in Fig. 3.

. This cut is such that the lugs .8 and 9, which lie one directly above the other, are on opv posite sides of the cut. Also, these cuts are so disposed that the lugs 6 and 9 are integral with one part of-the secondary and the lugs 7 and 8 are integral with the other part. The lugs 8 and 9 are .electrically'connected by a connecting member 31 lyingoutside the core 12. This connecting member 31 and the lugs 8 and 9 are secured together by means of bolts 32. This construction is such that the secondary current flows from the lug.6 half wayaround the annular secondary5 to the lug 9, then through the connecting member 31 to the lug 8, then half way around the annular secondary to the lug 7, then through the parts 25, 24, 23 and 15 and the parts to bewelded together to the lug 6. It will be seen that the secondary current in flowing over this path makes two'turns 'aro'undthe core 12.

The. apparatus thus constructed is preferably inclosed within a casing 33 of nonmetallic material. Such a casing of rectanadapted to engage a contact 39 connected to thepi imary coils to open and close the primary circuit of t-he transformer.

The severallugs 7, 8, 9 and 10 and the frame 15 are provided with openings therethrough, as shown at 41 in Fig. 2 and in dotted linesfin Fig. 1, for a cooling agent, such as water, whereby thetemperature of the secondary may be maintained at a sufficiently low point. These tubular openings may be' connected together by tubes\ 42,

which pass through the casing of the machine, these connections carrying the water of a suitable circulating system, whereby the secondary winding iscooled.

I In the operation of the machine the handle 22 is turned to raise the tool '24 and the parts to be Welded are then assembled between the tool 24 and bar 25; then by raising the handle 22 the tool 24 may be turned about its pivotal connection to'the frame 15 and forced into hard contact with the work. The operator then presses the end of the member 35 'so as to close the primary circuit, whereupon theyvelding current .flows in the secondary circuit. The path of this secondary-currentis such that the current flows twice around the core 12, completing the turn once through-the conducting member 31 and the second time through the work and the terminals of the machine. If parts of different thickness. are to be welded together a change is made in the connection of link 27 to disk 21.

, By reason of the construction of the inachine as herein set forth, the dimensions and weight of the'machine may be made very small by comparison with other machines of similar capacity. This small size isdue largely to the construct-ion of the secondary and the core in the manner above described and the winding of the primary coil directly upon this combined secondary and" core. The cutting of the casting for the secondary coil as'above setforth, thus requiring the secondary current to flow in a path making ing the combination of a secondary coil con stituting the frame of the machine, support- 1 peace:

two turns about the core, alsocontributes to the reduction in the size of the machine.

lfdesired, more turns in the secondary cir- Having described my invention, what clann as new therein and desire to'secure by Letters Patent of the United States is:

1. A portable welding machine comprising devicesfor the machine secured to said 0911, and a primary coil, a core and terminals connected to the secondary coilall mountedon the secondary coil, substantially asdset forth.

2. In a welding machine, the combination of a secondary coil constituting the frame of themachine, supporting devices for the machine secured to said cell, a primary coil'and a core mounted on the secondary-coil, terminals mounted on the secondary coil and connected thereto and means mounted onthe secondary coil for moving the terminals to; ward and away from each other, substantially as set forth. v

3. In a welding, machine, the combination of a secondary coil shapedto inclose a core, a core located therein, a primary coil encircling the secondary and core and terminals .connected to the secondary coil and movable toward and awa from each other, substantially as set forth. I

4. In a welding machine, the combination of a secondary coil shaped to inclose a core,

a core located therein, -a primary. coil encircling the secondary and core, terminals mounted on the secondary and connected thereto and means mounted on the secondary for moving the terminals toward and away from each other, substantially as set forth.

' 5. In a welding machine, the combination of an annular secondary coil, a core adjacent thereto, a primary coil inclosing the secondary and core and terminals connected'to the secondary coil and movable toward and away from each other, substantially as set fort.

6. In a welding machine, the combination of an annular secondary coil sha ed to inclose a core, a core inclosed there y, a rimary coilinclosing the core and secon ary coil, terminals mounted on and connectedto the secondary and means for moving the terminals toward .and away from each other, substantially as set forth.

of an annular secondary coil, a core consisting of wire wound on the secondary, a

primarycoil wound on the core an'd secondary, terminals mounted on and connected to the secondary and means for moving the terminals toward andaway from each other, substantially as set forth.

8 In awelding machine, the combination of'a secondary coil consisting of an annular secondary coll, a core consisting of' wire terminals toward and away from each-other, x

- substantially as set forth.-

' 9. In a welding machine, the combination of ,a secondary. coil,- integral lugs thereon at points intermediate-the terminals having openings therethrough for a cooling the dium, a primary coil and core associated with the secondary coil, connections to sald openings for carrying the cooling medium and terminals connected to the secondary coil and movabletoward and away from each other, substantially as set forth.

1O. In a welding machine, the combination of. a secondary coil and a core in cooperative relation thereto/a rimary coil wound thereon, the windings o the primary coil passing through the secondary coil and core, and terminals connected to the secondary coil'and movable toward and away from each other, substantially as set forth.

11. In a welding machine, an annular secondary coil having the continulty thereof interrupted at one point by a cut across one side of the coil, an annular core ad acent to the coil and a connecting member forming art of the secondary circuit, said member being connected to the secondar cell on opposite sides of the said out t erein and forming with said coil one turn about said core, substantially as set forth.

12. In a welding machine, an annular secondary coil having a cut across one side of the same theends'of which out are displaced circumferentially of the coil, terminals connected to the coil on opposite sides of; the cut and arranged one above the other in a line substantially parallel to the axis of the coil, and means for moving the terminals toable toward and away from the other, sub-' stantially asset fort 14. In awelding machine, an annular secondary formed in two parts,an annular core associated therewith, a connecting member connected to said parts and lying on the side of the core opposite therefrom and-two "parts and movable toward and away from 10 7 terminals each connected to one of saidparts each other, substantially as set forth. and movable toward and. awayIfrom each This specification signed and witnessed other, Isriilbstantilaally as sethforth. d this 20th day of February, 1913.

15. a we ing mac ine 'a secon ary formed in two arts, 9. connecting member JAMES GRAVELL' connected to sal parts and separated there- Witnesses: A, from between the points of connection to WM. J. EARNSHAW, said parts and terminals connected, to said 'BRUCE F. Ronnie 

